I found a cheaper version that looked identical on an online auction site, complete with Samsung branding, but it turned out to be a fake. The LED doesn't turn green when charging is complete, and the phone gets hot.
Much better to pay the few extra bucks and get the genuine product from MobileZap. The build quality is much better. I now have 2 of these in different parts of the house, and they work well with both my Galaxy S6 and S7.
Remember you'll need to supply the charger; it doesn't come with a charger.